Canolbarth Forest - Bad Magic Points

Thornbush, Dragontree and Stalkbrow are specifically noted by the elves as areas of malignant, rather than benign magic.“Wronglife” and “twisted magic” are elven names for these areas which have existed for centuries and show no sign of disappearing.
In these areas, the magic of Alfheim occasionally causes evil monsters to either be spontaneously generated or teleported in from somewhere else. These evil creatures proceed to roam around the forest – killing elves and devastating the plantlife. The elves have scouts and guards detailed to detect and kill these creatures, but many monsters evade immediate detection and escape to roam wreaking death and destruction. It is also said that the elves actually prefer to let the monsters wander for a while – it makes the hunt that much more interesting.

Sometimes though there are worse things than mere physical horrors occurring as in the case of Stalkbrow.